Tubing connectors for threadless pipe, tubing, conduit and like are known and have been widely used in the art. The tubes are mechanically connected by means of a threaded fitting which fits over an expansion on the tube end and are screwed together to clamp the expansion to the mating part. These known tubing connectors are exemplified by U.S. Pat. Nos. 2,522,194 and 3,494,643. These known tubing connectors have the disadvantage of being susceptible to leaking because gaps, inherent to the design, of significant size occur between the expansion, or flare, and fitting to allow the expansion to deform during assembly. The resultant deformation allows vibration and the like to loosen the fitting assembly and unseat the sealing surfaces, and repeated reassembly and sealing to other identical mating components is rendered impossible.
Tubes that are brazed to fittings via salt, flame, induction, or furnace braze processes or welded via magnesium insert gas, tungsten insert gas, or resistance welding processes are also known. These known processes are exemplified by U.S. Pat. No. 4,887,853. These known processes have the disadvantage of using large amounts of energy to heat and cool components, polluting the environment and requiring pre- and post-treatments and fluxes, all of which are hazardous, and produce a braze or weld joint that forever represents a leak path.
Fittings that are impact extruded onto tubes are known. These known processes have the disadvantage that great expense causes these processes to currently be commercially inviable.